In a communication system where multiple subscribers require a connection to a central communications node, techniques have been developed which provide channels between the subscribers and the communications node. In a communication system, such as a satellite-based communication system, it is desired that the satellite provide communication channels by generating receive and transmit antenna beams preferably in those directions where subscribers are located. This helps to minimize the resources which are needed to establish and maintain a communication channel between a terrestrial-based subscriber and the space-based communication satellite.
In communication systems, antenna beamforming techniques may be used to generate and steer communication beams toward areas occupied by terrestrial-based subscribers. Through the use of beamformers, receive and transmit communication beams can be generated to efficiently service only those areas of the earth occupied by subscribers. Typically, beamforming is performed at the carrier frequency or an intermediate frequency. However, performing the beamforming at the carrier or an intermediate frequency requires a level of complexity that is proportional to the bandwidth of the entire communication system node. Thus, in a typical satellite-based system, the complexity of the beamformer is proportional to the product of number of beams generated by the satellite multiplied by the available bandwidth per beam. Additionally, the satellite system is prone to generating transmit and receive beams that do not contain subscriber information. This additional complexity and inefficiency increases the cost of communication services to the subscribers.
Thus, what is needed are a method and system for efficiently generating transmit and receive communication beams using a reduced complexity beamformer.
What is also needed are a method and system for generating transmit and receive communication beams to service those areas of the earth occupied by subscribers.